Energy Survey and Saving otentials in the Building Sector City of Eggesin within the EU-project EffCoBuild Berliner Energieagentur GmbH Französische Str. 23 10117 Berlin Telefon 030 293330 0 Telefax 030 293330 99 e-mail: office@berliner-e-agentur.de compiled by Dipl.- Ing. Architekt Frank W. Lipphardt Cand. Wirt. -Ing. Sascha Brandt Dipl.- Ing. Claudia Alt roject-nr. 05 308 000 25/05/07
Inhalt 1 Conceptual Formulation 3 2 The City of Eggesin 3 2.1 Geography 3 2.2 Demography 4 2.3 Energy Supply Structures 5 3 Source of energy data 5 4 Residential Buildings 6 4.1 General Residential Building Stock 6 4.2 Individual Owned Building Stock 8 4.2.1 Building Stock Structures 8 4.2.2 Energy consumption of the private residential buildings - Evaluation of the questionnaire 10 4.2.3 Energy consumption of the private residential buildings assumptions 11 4.3 Communal Managed Building Stock 11 4.3.1 Structures of the Communal Building Stock 12 4.3.2 Energetic Quality 15 4.4 Energy Supply Structures 17 4.4.1 Individual Owned Building Stock 17 4.4.2 Communal Owned Building Stock 17 4.5 Electricity consumption of private households 18 5 ublic Buildings 18 5.1.1 Energetic Quality of the public buildings 21 6 Industrial Buildings, trade and services 24 7 Survey of the Actual A Energy consumption of Eggesin 25 8 Energy Saving otential Virtual ower lant 27 8.1 Approaches of the energy saving of the private residential buildings 28 9 Summary 29 Berliner Energieagentur GmbH Seite 2
EffCoBuilt 1 Conceptual Formulation It is planned to investigate the total energy demand of the city of Eggesin as well as the amount of energy consumed by the buildings. The building stock will be classified by its condition regarding the energy demand, and for each group of building the saving potential will be estimated. The estimation will be orientated at technical standard values and experience values of energy refurbishments of buildings in the region. The sum of the saving potentials in all building groups results in the total energy saving potential of the community. 2 The City of Eggesin 2.1 Geo eography Eggesin is situated in the north-east of the Federal Republic of Germany near the Baltic sea and the olish border. This location of Eggesin causes structural problems, because until now it is still economically cut off of the polish back country and the nearest large City Stettin, because of a still shut border crossing. The region is characterized by agriculture on the one side and few industries on the other side. icture 2-1: Geographical position of Eggesin in Germany The town by itself exhibits strongly fragmented structure (see figure below). Especially due to the post war construction activities in the German Democratic Republic Eggesin never developed a real city centre. In addition the town is Berliner Energieagentur GmbH Seite 3
burdened by large, in most parts deserted military bases due to the need to convert them into facilities of use or to demolish them. icture 2-2: Map of Eggesin 2.2 Demography The town of Eggesin is a small town with now about 6.000 inhabitants. After the Federal Armed Forces had closed their barracks in the beginning of this decade, the population has decreased drastically. The following figure shows the development of the population of Eggesin (except for military staff). Eggesin opulation Inhabitants 9.000 8.000 7.000 6.000 5.000 4.000 3.000 2.000 1.000 0 1990 1995 2000 2005 2010 2015 2020 Year figure 1: development of the population in Eggesin Berliner Energieagentur GmbH Seite 4
It is anticipated that the population will decrease further in the future caused by general migration from smaller to bigger towns and from East Germany to West Germany. 2.3 Energy Supply Structures Beside a municipal owned district heating grid, that provides the majority of the communal managed apartments and some public buildings with heat, Eggesin is supplied with gas, liquid gas and electricity by only one regional supplier E.ON edis. Fuel oil, that is also used, is provided by private dealers. 3 Source of energy data The source of energy data can be described as follows: GWZ 1995 (Building and dwelling counting 1995) ISEK 2005, Eggesin (Integrated Concept of municipal development) 200 Questionnaires for residential buildings: condition of the building, state of refurbishment and energy consumption, distributed to building owners unfortunately the reflux was very poor: only the 66 communal owned residential houses and 20 one- or two-family houses City of Eggesin (data of public buildings, new constructed and dismantled buildings): Heat and electricity consumption for public buildings (natural gas, oil, district heating, electricity) Heat consumption and auxiliary electricity consumption for communal residential buildings (natural gas, district heating, electricity) Heat and electricity consumption for the three industrial companies (oil, electricity) Input in the local district heating (wood chips and oil) Own calculation and estimation The local supplier of gas and electricity however rejected the provision of supply data. Moreover the accurate number of private buildings, flats and their surface was not available. Therefore some estimation had been done: From the given number of buildings and flats in the last census 1995 the since then new constructed buildings and number of flats known by the community administration were added, whereas deconstructed buildings and flats were subtracted. The number of flats per building and the average surface of the flats were estimated. The following table shows the assumptions: One family house Two family house Multy-family house 3-6 flats Multy-family house 7-12 flats 1 flat / building 2 flat / building 4,5 flat / building 8 flat / building 120 m²/flat 100 m²/flat 80 m²/flat 70 m²flat Berliner Energieagentur GmbH Seite 5
4 Residential Buildings Eggesin has quite an eventful history. In 1995 there have been still 3.280 apartments in total in town. Due to the shutdown of the military base that came along with a loss of jobs and shrinking population numbers there was a need to compensate the lower demand for apartments. Therefore the town removed and dismantled several buildings with 482 apartments in total until 2005. On the other hand 154 buildings with 235 apartments mostly one and two family houses were built since then. Eggesin still exhibits an oversupply of living space. Hence an ongoing process of deconstruction can be expected. It becomes clear that Eggesin features special structural and demographic conditions that have to be taken into account in a comprehensive analysis regarding energy efficiency, especially in an energy saving potential examination which includes long-term energy efficiency measures. 4.1 General Residential Building Stock The residential building stock in Eggesin is characterized by three main phases of development. Before World War 2 Eggesin exhibited typical small town structures with a mix of one and two family houses and small multi family residences. After the war Eggesin became one of the main garrison towns in the former German Democratic Republic. New jobs came in town along with the military and the population rose fast. In order to meet the growing demand for apartments big multifamily residences have been erected. The third phase happened after the two German states reunified. This time was characterized by moderate new construction activities. Mainly one and two family houses and small multifamily houses have been erected in this period. age structure of the residential building stock 600 500 400 year of construct. 300 200 100 0-1918 1919-48 1948-68 1969-81 1982-90 1990-95 nach 1995 apartments buildings numbers of build./apartm. figure 2: age structure of the entire residential building stock (according to GWZ 1995, ISEK 2005) Berliner Energieagentur GmbH Seite 6
The figure above illustrates the age structure of the entire residential building stock in Eggesin. The number of apartments built in a period gives an idea of the seize of the buildings that were erected in different decades. The seize structure of the entire residential building stock in Eggesin is demonstrated by the next graphic. One and two family houses but in particular one family houses represent the biggest part of the residential building stock. Although multifamily residences are in terms of numbers by far the minority, they have in total more apartments than one and two family houses together. This is particularly due to the size of those multifamily residences that were erected in the 70s and 80s of the last century. They have in general more than 10 apartments per building. seize structure of the residential building stock number of build./apartm. 1.400 1.200 1.000 800 600 400 200 0 one/two fam.res. multifam.res. 3-6 WE multifam. res. 7-12 WE multifam.res. 13-20 WE apartments buildings seize figure 3: seize structure of the residential building stock (according to GWZ 1995, ISEK 2005) In order to create effective strategies and campaigns that support to overcome investment barriers regarding energy efficiency measure, it is necessary to identify the main stakeholders in the housing business. The following graphic delivers insight into the property structures of the residential building stock. Berliner Energieagentur GmbH Seite 7
property structures of buildings municipilaty 21% others 8% individual 71% figure 4: property structures of the residential building stock in Eggesin (updated on the basis of GWZ 2005) The figure above makes clear that the majority of buildings in Eggesin is owned by individuals. That is not surprising as one and two family houses represent the by far biggest part of the building stock. Even though the city of Eggesin owns only about 21% of the total residential building stock, its buildings represent almost 50% of all apartments in the municipality. To sum up, individuals and the city of Eggesin are the main actors in the housing industry. Therefore it is sufficient to look at the individual and communal owned building stock in order to examine the energy quality of the entire building stock in Eggesin. About 8% of all buildings are owned by others like another housing society, Churches, etc. However, considering the size of those buildings, respectively the number of apartments per building, legal entities and others are only minor players in the housing business. 4.2 Individual Owned Building Stock 4.2.1 Building Stock Structures It is possible to say that one and two family houses in Eggesin exhibit similar characteristics concerning energy. That means, they have been erected more or less constantly, mostly during the last century with increasing energetic quality in particular during the last two decades. As described in the paragraphs above individual owners have a fraction of more than 70 % of the buildings whereas only 55 % of the existing apartments. The structure of age and size of the buildings can be calculated by subtraction of the communal residential buildings because these well-documented data are completely available of the total residential building stock. Berliner Energieagentur GmbH Seite 8
struture of age and size of the private residential buildings 250 number of buildings 200 150 100 50 EFH ZFH MFH 3-6 MFH 7-12 MFH 13-20 0-1918 1919-48 1948-68 1969-81 1982-90 1990-95 nach 1995 figure 5: structure of age and size of the private residential building stock in Eggesin (based on updated data of GWZ 2005 and questionnaire data related to communal residential buildings) As it can be seen, most of the private residential buildings are one and two family houses and were built until 1981. There are also several multi-family houses up to 12 apartments built in this period. No private residential building has more than 12 apartments and very few multi-family houses of private owners were built after 1995. The following pictures show several examples of the heterogeneous private building stock: icture 4-1: Non renovated row house icture 4-2: Renovated one-family house icture 4-3: Non renovated main street houses icture 4-4: Non insulated gables in the main street: Berliner Energieagentur GmbH Seite 9
Due the energy standard it could be said that many house owners have modernized their home and have combined necessary modernization measures with energy efficiency improvements. However, the extent of those improvements is difficult to estimate as the following chapter shows: 4.2.2 Energy consumption of the private residential buildings - Evaluation of the questionnaire To survey the energy consumption for the residential buildings, a questionnaire of energy data was developed for all project partners. In April 2006, 200 exemplars of the questionnaire were distributed by the city of Eggesin. 66 of them were filled in by the municipal housing company for its total stock; the reflux of private building owners however was poor with only 20 exemplars. They were evaluated concerning age, their standard of thermal insulation, implemented energy saving measures and heat consumption. The following figure shows the (un)expected results: specific heat energy consumption 400 350 300 unrenovated partly renovated completely renovated kwh/m²a 250 200 150 100 50 0 1880 1900 1920 1940 1960 1980 2000 year of construction figure 6: specific heat energy consumption of the private residential buildings (questionnaire) All buildings of the answering owners which were erected before 1980 have been at least partly renovated. In spite of this fact most of the older buildings have a specific heat energy consumption (including hot utility water) which lies above 200 kwh/m²a. The benchmarks of the newer buildings also vary remarkably although erected in a period with clear and rather strict building regulations. This evaluation shows that benchmarks are depending immensely from the individual constructional performance and behaviour. Therefore it seems permissible to revert to common benchmarks which are developed in scientific studies or from a larger source of data. Berliner Energieagentur GmbH Seite 10
4.2.3 Energy consumption of the private residential buildings assumptions To estimate the energy consumption of the private residential buildings assumptions were to be made. Therefore the method and used values were oriented to an evaluation of the Saxon institute of ecological and regional development in corporation with the consulting company invencon GmbH in 2003. In that study energy consumptions were calculated for different building types depending on their year of construction and state of renovation. By estimating the percentage of renovation status an average benchmark for the different types of building was developed. The following charts show the benchmarks: renovated non partly completely partly complet completely reduction compared with non renovated - 20% - 40% - 20% - 40% age / building typ One-family Two-family - 1918 306 229 184 282 212 141 1919-48 329 247 198 294 221 147 1948-68 235 176 141 212 159 106 1969-81 200 150 120 176 132 88 1982-90 206 154 124 188 141 94 1990-95 141 106 85 141 106 71 after 1995 118 88 71 118 88 59 sum 219 164 132 202 151 101 estimated pecentage 40% 50% 10% 50% 40% 10% avarage 183 171 chart 4-1: benchmarks for one- and two-family houses depending on year of construction and state of renovation and development of the average value renovated non partly completely partly complet completely reduction compared with non renovated - 25% - 40% - 25% - 50% age / building typ Multi-family 3-6 flats Multi-family 7-12 flats - 1918 224 168 134 229 172 115 1919-48 253 190 152 194 146 97 1948-68 212 159 127 188 141 94 1969-81 176 132 106 165 124 82 1982-90 194 146 116 176 132 88 1990-95 129 97 78 118 88 59 after 1995 118 88 71 sum 187 140 112 178 134 89 estimated pecentage 50% 40% 10% 50% 40% 10% avarage 160 152 chart 4-2: benchmarks for multi-family houses 3-6 respective. 7-12 depending on year of construction and state of renovation and development of the average value By estimating the rates of non, partly and completely renovated buildings the average end energy consumption value including the preparation of hot domestic water differs between 183 kwh/m²a for one-family houses and 152 for larger multifamily houses. The indicated benchmarks, which are corresponding with published values of many other studies, were used for the calculation for the heat energy consumption, including hot domestic water and losses through generation and distribution, of private residential buildings. 4.3 Communal Managed Building Stock Eggesin itself owns 1053 apartments. In addition it administers another 162 apartments, thus in total about 45% of the 2672 in the community. Four different Berliner Energieagentur GmbH Seite 11
building types represent the communal managed building stock. The following pictures show an old building in brick construction from the turn of the century, a typical post war building from the 50s, a multifamily building made with precast concrete slabs and a relatively new apartment building also erected with bricks. 4.3.1 Structures of the Communal Building Stock The communal managed building stock is dominated by buildings that have been erected in the 50s, the 70s and in the 90s (see figure 5). The city itself as the biggest initiator of new construction in Eggesin has tried to react on changes in the demand for living space during the time of socialism as much as today. The post war construction in the 50s and the erection of huge multifamily residences in the 70s and 80s was due to the population growth in Eggesin, whereas the construction activities in the 90s had its origin in an increasing demand for modern living space after the reunification of Germany. Hence even with decreasing population numbers and a continuously shrinking demand in the apartment market, new construction had been necessary. Berliner Energieagentur GmbH Seite 12
construction year structur 25 22 number of buildings 20 15 10 5 6 12 19 6 0 1 1900-1950 1951-1960 1961-1970 1971-1980 1981-1990 1991-today year of construction figure 7: construction year structure of the municipal operated building stock (questionnaire) As already mentioned, the communal operated building stock is dominated by multifamily residences (see figure 6). There is only one two-family building in the entire stock. More than 50% of the apartment building stock is represented by buildings with more than 10 apartments per building. Recapitulating, the communal administered building stock is characterized by a low number of relatively huge apartment buildings. seize structure number of buildings 40 35 30 25 20 15 10 5 0 36 29 1 1-2 units 3-10 units >10 unis number of apartments figure 8: seize structure of the municipal managed building stock (questionnaire) The construction type of the apartment buildings is determined by the year of their construction. For those buildings that have been erected until the end of the 60s and after 1990 the brick construction is typical, whereas all apartment houses Berliner Energieagentur GmbH Seite 13
that were built up in the 70s and 80s are made with precast concrete slabs, the so called industrial construction. Since the latter construction type is seen as the less preservable one and was characterized by high vacancy in the 90s, the deconstruction of apartment buildings in Eggesin was focused on those buildings. The following figure illustrates the distribution of the two construction types in the communal managed building stock. construction typ of buildings 39% 61% industrial construction brick construction figure 9: construction types in the communal managed building stock (questionnaire) The majority of industrial constructed buildings that had not been deconstructed were modernized in the 90s along with comprehensive energy efficiency measures like the insulation of external walls and the replacement of all windows with new efficient ones. Also all other apartment buildings in the municipal managed building stock like the older brick buildings have been updated in accordance with the then generalities regarding energy efficiency and emission standards. Only three industrial constructed buildings are still unimproved, since a need for cheap living space has been identified that prohibit both the deconstruction and the modernization of those buildings. Figure 8 shows that in 1995 the first modernization activities in the municipal administrated building stock took place, and it had its peak in 1998. It ended in 2000 with the completion of the building stock modernization. The refurbishment has been necessary, in order to assure a profitable business in the future. Berliner Energieagentur GmbH Seite 14
building modernisation activities 25 number of buildings 20 15 10 5 0 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 year figure 10: modernisation activities in the communal managed building stock (questionnaire) Since the building stock of the municipality is almost completely modernized, the realization of further measures to improve the energy efficiency and in particular long-term measures seems to be unlikely. 4.3.2 Energetic Quality In order to assess the energy efficiency of the different building types within the municipal managed building stock, their specific heat consumption has to be examined. The following graphic shows the specific energy consumption of every single building. Berliner Energieagentur GmbH Seite 15
300 specific heat energy consumption of municipal residential houses 250 200 kwh/m²a 150 100 50 0 1890 1910 1930 1950 1970 1990 2010 year of construction figure 11: specific heat energy consumption of the communal managed apartment buildings (questionnaire) Apparently there is a trend towards lower heat energy consumption along with the construction year of the buildings. However, only a few apartment buildings reach the energetic quality standards of the German Energy Saving Directive (EnEV) for new apartment buildings. Even though also all buildings that have been erected before 1960 were improved in terms of energy efficiency, their heat energy consumption is still way higher than that of younger buildings, partly even twice that high. Those buildings still exhibit additional energy saving potential. Interestingly modernized industrial constructed buildings, although older, don t exhibit higher heat energy consumption figures than those buildings that have been built up in the 90s. It is likely that the more cost aware renters of those apartment buildings are one part of the reason for this phenomenon. Furthermore the big industrial constructed buildings exhibit a quite compact structure, which is an advantage for energy efficiency purposes. However, the figures document that refurbished industrial constructed buildings can be as energy efficient as new buildings. The benchmark averages 124 kwh /m²a. That corresponds with the average value of the technical guideline VDI 3807. However the guide value represents at 95 kwh/m²a including hot domestic water. Berliner Energieagentur GmbH Seite 16
4.4 Energy Supply Structures In addition to the energetic quality of buildings, the heat energy provision is crucial in an energy efficiency assessment of the community. 4.4.1 Individual Owned Building Stock One and Two family houses are characterized by a mixed heat supply structure. For the most part natural gas and heating oil are used in that part of the building stock in Eggesin. In addition many homes are equipped with wood fired stoves. The use of thermal solar energy is rare. The hot domestic water is sometimes produced by electrical boilers or geysers. As the local supplier e.on edis did not provide any data as mentioned before, the rates of the different energy sources had to been estimated. Therefore the available grid of the natural gas supply was studied. The use of district heating is known as the community runs the heat plant. The heat energy generation by oil was estimated to be equal as by natural gas. The remaining amount was distributed on other energy sources like wood coal and electricity. 4.4.2 Communal Owned O Building Stock By contrast the apartment buildings that are managed by the municipality are provisioned by a district heating grid or by natural gas fired central heating. The district heating grid that provides heat also for some public buildings is mainly supplied by a wood ship fired district heating plant. The following graphic illustrates the heat energy supply structure of the communal administered building stock. heating supply structure (by consumed energy) 1% 34% heating oil natural gas district heating 65% figure 12: heating supply structure in the communal managed building stock (questionnaire) Additionally to this innovative heating plant and small oil fired block heat and power plant, the city of Eggesin plans to build a new block heat and power plant Berliner Energieagentur GmbH Seite 17
fired with palm oil from Asia. This new plant shall enable the city to generate electricity that its public buildings consume. This supply concept is supposed to reduce the energy cost of the municipality compared to the electricity provision by the regional utility. 4.5 Electricity consumption of private households The electricity consumption of private households in Eggesin was assumed on average at 3.300 kwh/m²a. According to the experience of large electricity suppliers households in one- and two family houses consume on a higher, households in multi-family houses consume on a lower range. It was incorporated the majority of the tenants in the communal owned residential buildings are cooking with electricity. Basically the consumption in eastern Germany households is remarkable lower than in Western Germany households. Reasons should be the later equipment which is more energy efficient and the further developed sense for saving costs and resources. That is proved with the results of the market researchi institute forsa which evaluated numbers from the year 2003: Table 4-3: Comparison of electricity consumption of private households depending on Easter (Ost) Western (West) Germany and the number of persons per households (forsa 2003) 5 ublic Buildings Beside a number of apartment buildings that are managed by the city, Eggesin administers a number of public buildings: city council building elementary school secondary school vocational school with gymnasium recreational centre library fire department Berliner Energieagentur GmbH Seite 18
civil protection building building yard. However the vocational school is for the most administered by the district of Uecker-Randow. The following pictures show some of the public buildings. icture 5-1; City council building (source: www.eggesin.de) icture 5-2: Elementary school (source: www.eggesin.de) Berliner Energieagentur GmbH Seite 19
icture 5-3: Secondary school (source: www.eggesin.de) icture 5-4: Vocational school (www.eggesin.de) Berliner Energieagentur GmbH Seite 20
icture 5-5: Recreational centre for pupil (source: www.eggesin.de) icture 5-6: Fire department (source: www.eggesin.de) The public building stock in Eggesin is like the residential building stock represented by old and new brick constructed and industrial constructed buildings. Figure 11 gives an overview of the energy consumption of all public buildings over the year 2005 in Eggesin. 5.1.1 Energetic Quality of the public buildings building area (m²) consumption of electricity (kwh) specific consumption (kwh/ m²) heat energy supply consumption of heat energy (kwh) specific consumption (kwh/ m²) city council 1.130 44.070 39 district heating 225.006 199 vocational school 2.416 79.950 26 district heating 256.605 106 gymnasium 663 district heating 89.994 136 secondary school 5.100 58.800 12 oil-fired central heating 531.908 104 elementary school 2.115 31.860 15 oil-fired central heating 222.706 105 recreational centre 224 6.174 28 oil-fired central heating 51.124 228 library 940 11.940 13 district heating 154.007 164 fire department 1.966 7.889 4 natural gas-fired central heating 52.036 26 civil protection 1.230 2.804 2 natural gas-fired central heating 14.293 12 building yard 687 7.695 11 district heating 166.060 242 Summe 16.471 251.182 15 1.763.739 107 table 5-1: energy consumption of public buildings in Eggesin in 2005 (source: city of Eggesin) Beside the heat supply by the district heating grid, some buildings are provisioned by oil-fired or natural-gas fired central heating. The oil-fired boiler in the elementary school will be replaced by a natural gas-fired one in the near future. It is likely that this will happen to other oil-fired boilers as well. Berliner Energieagentur GmbH Seite 21
consumption of heat energy civil protection building fire department building yard city council recreational centre library vocational school elementary school gymnasium secondary school figure 13: proportional heat energy consumption of public buildings in Eggesin (source: city of Eggesin) The figure above illustrates the proportional heat energy consumption of the single public building in comparison with the total heat consumption of all public buildings. It becomes apparent that the city council building and the three schools are the major consumer of heat energy. The other 5 public buildings in Eggesin do not even represent 25% of the total heat energy consumption. consumption of electricity civil protection building fire department recreational centre library building yard city council elementary school secondary school vocational school with gymnasium figure 14: proportional electricity consumption of public buildings in Eggesin (source: city of Eggesin) Berliner Energieagentur GmbH Seite 22
The electricity consumption of public buildings shows almost the same situation (see figure 13). Again, the city council building and the three schools are the biggest consumer. In order to assess the energy consumption figures, it is necessary to compare them with reference values. Such figures for non-residential buildings exist in the German Energy Saving Directive (see figure below). Building Reference value for heat energy consumtion (kwh/m²a) Reference value for electricity consumption (kwh/m²a) city council 105 24 vocational school 120 18 gymnasium 150 12 secondary school 135 14 elementary school 135 14 recreational centre 160 20 library 105 32 fire department 120 16 civil protection 120 16 building yard 165 18 figure 15: reference values for non-residential buildings (source: Entwurf vom 06.09.06 der Richtlinie für Energieverbrauchskennwerte Nichtwohngebäude) These figures reflect the average specific consumption of different non-residential building types in Germany and thus allow a sensible comparison. kwh/m²a 300 250 200 150 100 50 0 city council heat energy consumption in comparison with reference values vocational school gymnasium secondary school elementary school recreational centre library fire department civil protection building building yard real consumption reference consumption figure 16: heat energy consumption of public buildings in comparison with reference values (source: city of Eggesin) Berliner Energieagentur GmbH Seite 23
Assessing the figures in detail (see figure 14) the relatively high heat energy consumption of the city council building and the recreational centre become noticeable as much as the ones of the library and the building yard. However, the latter have to be relativized, since the library building is also used for a number of other purposes and the building yard is in general difficult to compare due to its heterogeneous composition of open and closed halls. The same is true for the fire department and the civil protection building. The result of the comparison with reference values seems to be quite good, but that does not necessarily mean that the buildings meet very high energetic quality standards. It is essential to analyze those buildings individually, since their use intensity can not be expected to be a fix value as it is expected in a comparison with reference values. Apparently those comparisons might exhibit a bigger issue when it is necessary to work with reference values and benchmarks, especially in the assessment of nonresidential buildings. specific electricity consumption in comparison with reference values kwh/m²a 45,00 40,00 35,00 30,00 25,00 20,00 15,00 10,00 5,00 0,00 city council vocational school with gymnasium secondary school elementary school recreational centre library fire department civil protection building building yard real consumption reference consumption figure 17: electricity consumption of public buildings in comparison with reference values Examining the electricity consumption of public buildings, the city council building and the recreational centre stand out again with relatively high specific consumption figures as much as the vocational school. The assessment of the last 4 buildings, the library, the fire department, the civil protection building and the building yard is again only possible to a limited extent. 6 Industrial Buildings, trade and services In the community of Eggesin three larger industrial companies are situated: The companies were asked for energy consumption data which they kindly delivered: Berliner Energieagentur GmbH Seite 24
Energy source Heat energy electricity [MWh/a] [MWh/a] Hanning-Werke oil 2.211 3.076,5 Instrutec / BfW oil 510 128 Greese-Beton 411 Sum 2.721 3.670 Table 6-1: Table of the energy consumption of the industrial companies As it is recognizable the large company Hanning-Werke a producer of electric motors with the most employees is the largest consumer by far, followed by Instrutec which is a producer of gynecological instruments. The concrete company Greese needs electrical power for its production. The consumption of smaller trading and service companies was estimated by the number of companies, heated areas average values for heat and electricity. 7 Survey of the Actual Energy consumption of Eggesin The above developed and shown approaches for the energy consumption of the community of Eggesin can be summarised in the following table and graphs: Energy source Natural Gas District heating (80% wood, 20%oil) Electricity (Heat) Wood Coal Electricity (households) Sector Oil Sum rivate residential buildings 16.670 16.670 1.050 490 630 140 5.670 41.310 Communal residential buildings 2.450 33 6.940 3.210 12.640 Industry, Trade and Services 700 3.420 250 4.275 8.645 ublic Buildings 66 800 1.320 250 2.440 Sum (MWh/a] 19.890 20.920 9.300 740 630 140 13.400 65.030 CO 2 -factor [t CO 2 /MWh ] 0,20 0,27 0,04 0,65 0,00 1,00 0,65 CO 2 -Emissions [t/a] 3.980 5.650 50 370 480 0 140 8.700 19.230 Table 7-1: The following two graphs visualize the results: Berliner Energieagentur GmbH Seite 25
Estimated Division of the Energy Sources in Eggesin (2005) oil 21% natural gas 31% district heating (80% wood, 20%oil) 1% 1% electricity (heating) wood 14% coal electricity (households) 32% Graph 7-1: Division of the energy sources in Eggesin (2005) MWh/a End Energy Consumption Eggesin due Sectors und Energy Sources 50.000 electricity (households) 40.000 coal 30.000 wood 20.000 electricity (heating) 10.000 0 rivate residential buidlings Communal residential buidlings Industry, Trade and services ublic buildings district heating (80% wood, 20%oil) Graph 7-2: Energy consumption and greenhouse gas emissions of Eggesin depending on energy sources and Sectors The last graph indicates that the sector of private households is the largest consumer of energy. Though a similar number of flats, the state of renovation and insulation of the thermal building shell connected with an unfavourable form factor leads to a significant higher consumption. The electricity consumption is higher due to a higher specific consumption and a higher rate of auxiliary energy in smaller private houses. Berliner Energieagentur GmbH Seite 26
It has to be noted that the losses of the generation and distribution of the communal heating plants as well as the public lighting was not calculated within this energy survey. 8 Energy Saving otential Virtual ower lant icture 8-1: The energy saving plant of Eggesin The final energy saving potentials are summarized in the picture above: the energy saving plant of Eggesin. It visualizes the high potential in private households with about 2.700 MWh/a (heat energy of private residential buildings and electricity of all households), followed by potentials of the industry of about 650 MWh/a. The communal buildings residential and public buildings together offer the lowest potential due to measures already performed. The different modules and approaches of the power plant are described below: No Modules Savings percentage MWh/a 1 Auxiliary electricity communal residential buildings 10% 5 2 ower balance communal residential buildings 2% 60 3 Heat consumption communal residential buildings 5% 360 4 ower balance in private buildings 3% 200 5 Heat energy in private buildings absolute 2.400 6 Industry electricity 10% 330 7 Industry heat energy 10% 320 8 Electricity public buildings absolute 50 9 Heat public buildings absolute 140 Berliner Energieagentur GmbH Seite 27
No Approach 1 Energy efficient pumps in case of exchange 2 Energy efficient behaviour, equipment, no stand-by losses 3 Dismantling of buildings and energy efficient maintenance 4 Energy efficient behaviour, equipment, reduction of stand by losses 5 3% of the buildings will be completely renovated (thermal shells) within the next 10 years, 20% will be partly renovated detailed approaches see below 6 Energy efficient machines in case of investments and lighting 7 Successive insulation measures (Hanning-Werke u. Instrutec) 8 Reduction of the electricity consumption to guide values (moves, lighting) 9 Reduction of the heat consumption to guide values (moves into energy efficient buildings Table 8-1: Modules of the energy saving plant and their approaches 8.1 Approaches of the energy saving of the private residential buildings The following approaches were used to calculate the heat energy saving potential: renovated non partly completely partly complet completely reduction compared with non renovated - 20% - 50% - 20% - 50% age / building typ One-family Two-family - 1918 306 229 153 282 212 141 1919-48 329 247 198 294 221 147 1948-68 235 176 141 212 159 106 1969-81 200 150 120 176 132 88 1982-90 206 154 124 188 141 94 1990-95 141 106 85 141 106 71 after 1995 118 88 71 118 88 59 sum 219 164 127 202 151 101 estimated pecentage 30% 55% 15% 30% 55% 15% avarage 175 159 Table 8-2: benchmarks for one- and two-family houses depending on the age of construction and state of renovation and developing of the average value renovated non partly completely partly complet completely reduction compared with non renovated - 25% - 50% - 25% - 50% age / building typ Multi-family 3-6 flats Multi-family 7-12 flats - 1918 224 168 112 229 172 115 1919-48 253 190 152 194 146 97 1948-68 212 159 127 188 141 94 1969-81 176 132 106 165 124 82 1982-90 194 146 116 176 132 88 1990-95 129 97 78 118 88 59 after 1995 118 88 71 sum 187 140 109 178 134 89 estimated pecentage 30% 45% 25% 30% 45% 25% avarage 146 136 Table 8-3: benchmarks for multi-family houses 3-6 respective. 7-12 depending on the age of construction and state of renovation and developing of the average value In comparison with the indicated benchmarks in chapter 4.2.3 the average of the end energy consumption of the different residential building types sank as follows: Berliner Energieagentur GmbH Seite 28
Building type Actual average benchmark Set average benchmark Reduction One-family 183 kwh/m²a 175 kwh/m²a 4 % Two-family 171 kwh/m²a 159 kwh/m²a 7 % Multi-family 3-6 flats Multi-family 7-12 flats 160 kwh/m²a 146 kwh/m²a 9 % 152 kwh/m²a 136 kwh/m²a 10 % Table 8-4: Comparison of the actual and the set average end energy consumption of private residential buildings in Eggesin The relative changes of average benchmarks of the end energy consumption of private residential buildings amount between 4 10 %. This seems not to be very ambitious. Nevertheless due the specific circumstances in Eggesin, it appears realistic. 9 Summary The municipality of Eggesin is situated in north eastern Germany with the frequently existing problems of sparsely populated regions in general and specific circumstances: Due to the move of the big military base, the population number was strongly decreasing in the last few years. The residential building stock is divided up between private owned buildings with one- and two-family houses on the one hand and communal owned multi-family houses on the other hand. Whereas the private residential buildings represent 70 % of the buildings, they offer only about the half of the available apartments. The other half is situated within the buildings stock of the communal owned housing company within 20 % of the buildings, mostly of them large multi-family blocks. While the communal owned building stock (residential as well as public buildings) was comprehensively renovated mainly in the 90s, the renovation state of the private houses is extremely heterogeneous and clearly lower than the communal owned buildings. That is why the energy saving potential is the highest in the sector of the private owned buildings. Nevertheless, and due to the financial situation of most of the owners it is not expected that the renovation rate will increase quickly on a high state. The industrial building sector is not large due to many closings of companies in the 90s. The remaining companies exhibit a remarkable energy saving potential concerning the thermal envelope, the production facilities and the technical building equipment (e.g. lighting). Berliner Energieagentur GmbH Seite 29